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Investment Securities (Investments In Private Equity Funds Subject to Lock-Up Periods) (Details) - Private equity security $ in Millions | Sep. 30, 2018 USD ($)
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Debt and Equity Securities, FV-NI [Line Items] |
Other long-term investments | $ 92.0
1-3 years |
Debt and Equity Securities, FV-NI [Line Items] |
Other long-term investments | 14.2
3-5 years |
Debt and Equity Securities, FV-NI [Line Items] |
Other long-term investments | 5.0
5-10 years |
Debt and Equity Securities, FV-NI [Line Items] |
Other long-term investments | 55.9
Greater than 10 years |
Debt and Equity Securities, FV-NI [Line Items] |
Other long-term investments | $ 16.9

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